London (CNN) -- Way back in the mists of time, when schoolkids were expected to learn seemingly endless lists of facts off by heart, they chanted a poem to remember the names of England's kings and queens. "Willie, Willie, Harry, Ste," it began. "Harry, Dick, John, Harry three / One, two, three Neds, Richard two / Harrys four, five, six, then who?" It then ended with the most recent monarchs: "Edward seven, George and Ted / George the sixth, now Liz instead." Of course, it's not done that way any more, but if it were, which name would make it into the next verse? We know that "Charles" and "William" will follow "Liz," but which name will follow theirs?